#include<stdio.h>
#include<string.h>
void swap( int *pa, int *pb ) 
{
    int pt;
    pt = *pa, *pa = *pb, *pb = *pa;
}
int main(void)
{    
    int x=1, y=2;
    swap(&x, &y);
    printf("%d%d", x, y);
}
